Catching the Warning Signs of DVT

Jul 1, 2010

In the United States, more people die each year from pulmonary embolism (PE) than motor vehicle accidents, breast cancer, or AIDS. Most PEs are complications of deep vein thrombosis (DVT). In fact, more than 2 million Americans suffer from DVT each year, with over half of these individuals developing their DVT complications in the hospital or in the 30 days after hospitalization. While the connection between the risk of DVT, cancer, and cancer treatment is not fully understood, the literature suggests that approximately 10% of individuals who present with DVT or PE will have a cancer diagnosis within 2 years of the thrombotic episode.

Other factors that increase the risk of DVT in patients with cancer are those whose disease has metastasized and those who are receiving chemotherapy. Furthermore, it has been reported that the probability of death within about 6 months of initial hospital admissions is over 94% for those who had venous thromboembolism and malignant disease compared with a rate of less than 40% for those with cancer alone.

What Oncology Nurses Can Do

From an historical perspective, DVT has been more closely related to surgical conditions. As such, routine attention to DVT risk has been given primarily to surgical patients; these individuals would be given compression stockings, prophylaxis, or other treatment. Now, there is heightened awareness that medical patients are also at risk for DVT. In addition to a cancer diagnosis, multiple risk factors and triggering events are associated with DVT, including increasing age, immobility, stroke, paralysis, previous DVT, major surgery, trauma, obesity, and inherited clotting predisposition, among others.

Oncology nurses should be aware of risk factors and what puts patients at high risk for DVT. They should also incorporate a DVT assessment into overall histories and physical exams. The Wells model (Table) for pre-test probability assessment for DVT can be performed quickly and efficiently by nurses. Patients who score 3 points or greater are considered high risk for DVT. Although DVT may occur without obvious symptoms, primary healthcare providers should be notified if patients are experiencing symptoms (eg, pain, swelling, tenderness, discoloration/ redness of the affected area, and skin warm to the touch).

DVT Awareness & Prophylaxis

DVT-related PE is the most common cause of preventable hospital death, yet only about a third of patients who have risk factors for blood clots receive prophylaxis. Without proper prophylaxis, the range of DVT risk is from 10% to 26% in general medical patients. Since nurses have the most contact with patients, it